Ricardo Carvalho felt Spain's winning goal against his Portugal side on Tuesday night was offside.
David Villa's strike just after the hour was the difference between the two sides in an entertaining yet tight game in Cape Town, but Chelsea man Carvalho was upset afterwards that the Barcelona forward was not flagged.
'What went wrong? The goal was offside a little bit!' the 32-year-old said afterwards. 'I think we had bad ball possession and they created more. They were more dangerous and played on the counter-attack.
'In these types of games you have to play better offensively and be compact defensively. To create more goals you have to play better.'
It was the first time Portugal had conceded at this World Cup, but equally it was the third game in four where they had not scored, goalless draws in the groups against Ivory Coast and Brazil sandwiching a 7-0 thrashing of North Korea.
'In that game we showed that we could create a lot of chances to score goals, but we couldn't score against Ivory Coast and Brazil, and today,' Carvalho said.
'Offensively we have to improve and play better as a team. We have to defend as a team and attack as a team. The back four needs to try and help the players up front to create more chances.'